The MWG 90 Rounder high capacity magazine for the AR-15/M16 provides you with the finest in state-of-the-art high capacity magazine design. The 90 Rounder's innovative snail-drum design and advanced space-age materials are combined to create a very light, completely reliable, low maintenance, high capacity magazine that will withstand a level of heavy field use that would destroy a metal magazine, while weighing 33% less. The 90 Rounder for the AR-15/M16 is designed for 5.56mm NATO or .223 Remington ammunition. The 90 Rounder for the AR-15/M16 is designed to be close to maintenance free. Never remove the silver-gray Teflon lubricant powder. Never Use any oil-based lubricant. Never disassemble MWG products, and never disassemble the 90 Rounder for the AR-15/M16 . The 90 Rounder for the AR-15/M16 contains small parts & springs that may cause injury if improperly released. If repairs are required, return the magazine to MWG Company for repair. Any disassembly, alteration will void warrant